ppc_cpu_compare_class_pvr_mask() should match the best CPU class in the
family, because it is used by the KVM subsystem to find the host CPU
class. Since commit 03ae4133ab ("target-ppc: Add pvr_match()
callback"), it matches any class in the family (the first one in the
comparison list).
Since commit f30c843ced ("ppc/pnv: Introduce PowerNV machines with
fixed CPU models"), pnv has relied on pnv_match having these new
semantics to check machine compatibility with a CPU family.
Resolve this by adding a parameter to the pvr_match function to select
the best or any match, and restore the old behaviour for the KVM case.
Prior to this fix, e.g., a POWER9 DD2.3 KVM host matches to the
power9_v1.0 class (because that happens to be the first POWER9 family
CPU compared). After the patch, it matches the power9_v2.0 class.
This approach requires pnv_match contain knowledge of the CPU classes
implemented in the same family, which feels ugly. But pushing the 'best'
match down to the class would still require they know about one another
which is not obviously much better. For now this gets things working.
Fixes: 03ae4133ab ("target-ppc: Add pvr_match() callback")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220731013358.170187-1-npiggin@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The 'resume_as_sreset' attribute of a cpu is set when a thread is
entering a stop state on ppc books. It causes the thread to be
re-routed to vector 0x100 when woken up by an exception. So it must be
cleared on reset or a thread might be re-routed unexpectedly after a
reset, when it was not in a stop state and/or when the appropriate
exception handler isn't set up yet.
Using skiboot, it can be tested by resetting the system when it is
quiet and most threads are idle and in stop state.
After the reset occurs, skiboot elects a primary thread and all the
others wait in secondary_wait. The primary thread does all the system
initialization from main_cpu_entry() and at some point, the
decrementer interrupt starts ticking. The exception vector for the
decrementer interrupt is in place, so that shouldn't be a
problem. However, if that primary thread was in stop state prior to
the reset, and because the resume_as_sreset parameters is still set,
it is re-routed to exception vector 0x100. Which, at that time, is
still defined as the entry point for BML. So that primary thread
restarts as new and ends up being treated like any other secondary
thread. All threads are now waiting in secondary_wait.
It results in a full system hang with no message on the console, as
the uart hasn't been init'ed yet. It's actually not obvious to realise
what's happening if not tracing reset (-d cpu_reset). The fix is
simply to clear the 'resume_as_sreset' attribute on reset.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220617095222.612212-1-fbarrat@linux.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
This patch adds tcg accessors for 2 SPRs which were missing on P10:
- the TBU40 register is used to write the upper 40 bits of the
timebase register. It is used by kvm to update the timebase when
entering/exiting the guest on P9 and above. The missing definition was
causing erratic decrementer interrupts in a pseries/kvm guest running
in a powernv10/tcg host, typically resulting in hangs.
- the missing DPDES SPR was found through code inspection. It exists
unchanged on P10.
Both existed on previous versions of the processor and a bit of git
archaeology hints that they were added while the P10 model was already
being worked on so they may have simply fallen through the cracks.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20220411125900.352028-1-fbarrat@linux.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
PPC_INTERRUPT_EBB is a new interrupt that will be used to deliver EBB
exceptions that had to be postponed because the thread wasn't in problem
state at the time the event-based branch was supposed to occur.
ISA 3.1 also defines two EBB exceptions: Performance Monitor EBB
exception and External EBB exception. They are being added as
POWERPC_EXCP_PERFM_EBB and POWERPC_EXCP_EXTERNAL_EBB.
PPC_INTERRUPT_EBB will check BESCR bits to see the EBB type that
occurred and trigger the appropriate exception. Both exceptions are
doing the same thing in this first implementation: clear BESCR_GE and
enter the branch with env->nip retrieved from SPR_EBBHR.
The checks being done by the interrupt code are msr_pr and BESCR_GE
states. All other checks (EBB facility check, BESCR_PME bit, specific
bits related to the event type) must be done beforehand.
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220225101140.1054160-4-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This is an exclusive TCG helper. Gating it with CONFIG_TCG and changing
meson.build accordingly will prevent problems --disable-tcg and
--disable-linux-user later on.
We're also changing the uses of !kvm_enabled() to tcg_enabled() to avoid
adding "defined(CONFIG_TCG)" ifdefs, since tcg_enabled() will be
defaulted to false with --disable-tcg and the block will always be
skipped.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220225101140.1054160-2-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Let's leave cpu_init with just generic CPU initialization and
QOM-related functions.
The rest of the SPR registration functions will be moved in the
following patches along with the code that uses them. These are only
the commonly used ones.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-28-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
These will need to be accessed from other files once we move the CPUs
code to separate files.
The check_pow_hid0 and check_pow_hid0_74xx are too specific to be
moved to a header so I'll deal with them later when splitting this
code between the multiple CPU families.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-27-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The following patches will move CPU-specific code into separate files,
so expose the most used SPR registration functions:
register_sdr1_sprs | 22 callers
register_low_BATs | 20 callers
register_non_embedded_sprs | 19 callers
register_high_BATs | 10 callers
register_thrm_sprs | 8 callers
register_usprgh_sprs | 6 callers
register_6xx_7xx_soft_tlb | only 3 callers, but it helps to
keep the soft TLB code consistent.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-25-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Initial intent for the spr_tcg header was to expose the spr_read|write
callbacks that are only used by TCG code. However, although these
routines are TCG-specific, the KVM code needs access to env->sprs
which creation is currently coupled to the callback registration.
We are probably not going to decouple SPR creation and TCG callback
registration any time soon, so let's rename the header to spr_common
to accomodate the register_*_sprs functions that will be moved out of
cpu_init.c in the following patches.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-24-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This is just to have 755-specific registers contained into a function,
intead of leaving them open-coded in init_proc_755. It makes init_proc
easier to read and keeps later patches that touch this code a bit
cleaner.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-16-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The 745 and 755 can share the HID registration, so move it all into
register_755_sprs, which applies for both CPUs.
Also rename that function to register_745_sprs, since the 745 is the
earliest of the two. This will help with separating 755-specific
registers in a subsequent patch.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-14-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
We're considering these two to be in different CPU families (6xx and
7xx), so keep their SPR registration separate.
The code was copied into register_G2_sprs and the common function was
renamed to apply only to the 755.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-9-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Make sure that every register_*_sprs function only has calls to
spr_register* to register individual SPRs. Do not allow nesting. This
makes the code easier to follow and a look at init_proc_* should
suffice to know what SPRs a CPU has.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-6-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The /* XXX : not implemented */ comments all over cpu_init are
confusing and ambiguous.
Do they mean not implemented by QEMU, not implemented in a specific
access mode? Not implemented by the CPU? Do they apply to just the
register right after or to a whole block? Do they mean we have an
action to take in the future to implement these? Are they only
informative?
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20220216162426.1885923-2-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The PowerPC 601 processor is the first generation of processors to
implement the PowerPC architecture. It was designed as a bridge
processor and also could execute most of the instructions of the
previous POWER architecture. It was found on the first Macs and IBM
RS/6000 workstations.
There is not much interest in keeping the CPU model of this
POWER-PowerPC bridge processor. We have the 603 and 604 CPU models of
the 60x family which implement the complete PowerPC instruction set.
Cc: "Hervé Poussineau" <hpoussin@reactos.org>
Cc: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20220203142756.1302515-1-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The 602 was derived from the PowerPC 603, for the gaming market it
seems. It was hardly used and no firmware supporting the CPU could be
found. Drop support.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
